Transmission apparatus by which power is transmitted between the rotating shaft of a prime mover and another shaft is well known to those skilled in the art, and there are many patents and other references available for many different transmission apparatus.
It is known to connect opposed shafts by a friction clutch as shown by U.S. Pat. No. 2,385,864 to Knoblock. Also, over-running clutches are known as shown in Stibbe, U.S. Pat. No. 3,563,352 and Bentley U.S. Pat. No. 3,762,519.
Sipprell, U.S. Pat. No. 1,965,673 discusses automatic clutch devices for transmitting power and discloses disks having cam faces thereon for axially moving the disk. Horn, U.S. Pat. No. 2,915,156, and Swahnberg, U.S. Pat. No. 2,490,172, disclose a friction clutch having balls received within grooves that are arranged to provide an over-running clutch. Moreover, many differential mechanisms are old in the art as shown by the above patent to Knoblock and Stibbe.
None of the prior art known to Applicant, however, provides a practical and inexpensive drive system wherein a power source has opposed shaft ends, each connected to turn an axle of a pair of axles and thereby transmit power with a force that is proportional to the torque delivered to the driven member, and to provide a differential action having positive traction mode and a free wheeling mode in the manner set forth herein. Hence, there is no transmission to be found in the prior art that is similar in operation and structure to the transmission set forth herein.